docs: def print_usage(actions):
      """Print the usage information.  (Help screen)"""
      actions = actions.items()
      actions.sort()
      print('usage: %s <action> [<options>]' % basename(sys.argv[0]))
      print('       %s --help' % basename(sys.argv[0]))
      print()
      print('actions:')
      for name, (func, doc, arguments) in actions:
          print('  %s:' % name)
          for line in doc.splitlines():
              print('    %s' % line)
          if arguments:
              print()
          for arg, shortcut, default, argtype in arguments:
              if isinstance(default, bool):
                  print('    %s' % (
                      (shortcut and '-%s, ' % shortcut or '') + '--' + arg
                  ))
              else:
                  print('    %-30s%-10s%s' % (
                      (shortcut and '-%s, ' % shortcut or '') + '--' + arg,
                      argtype, default
                  ))
          print()